MERS situation update, March 2017

At the end of March 2017, a total of 1936 laboratory-confirmed cases of Middle East respiratory syndrome coronavirus (MERS-CoV), including 713 deaths (case–fatality rate: 36.8%) were reported globally; Majority of these cases were reported from Saudi Arabia (1575 laboratory-confirmed cases, including 639 deaths with a case–fatality rate of 40%).

During the months of February and March 2017, one hospital outbreak was reported from the Riyadh region resulting in 10 cases. No death was reported from this hospital cluster. The date of onset of illness of the index case was 26 February 2017 and that of the last laboratory-confirmed case was 11 March 2017. As no case was reported from this hospital cluster since 11 March and the interval period until the end of March is more than the double of the incubation period for MERS, it is safe to say that this hospital outbreak is essentially over.

Owing to improved infection prevention and control practices in the hospitals, the number of hospital-acquired cases of MERS has significantly dropped in 2015 and in 2016 compared to previous years. The demographic and epidemiological characteristics of the cases reported between January and March 2017 do not show any significant difference when compared with cases reported during the same period from 2013 to 2016.

The age group of those aged 50–59 years continues to be the group at highest risk for acquiring infection as primary cases. For secondary cases, it is the age group of 30–39 years who are mostly at risk. The deaths are higher in the age group of 50–59 years for primary cases and 70–79 years for secondary cases.